In the copending application of Bartolini et al referred to above, and incorporated herein by reference, organic volume phase holographic recording media are disclosed which are useful to store holograms in permanent form. Such media comprise certain .alpha.-diketones in an acrylic polyester resin, which .alpha.-diketones are capable of hydrogen atom abstraction with the polymer hosts during recording. Such reaction is irreversible and these media thus can be used as high density information storage media which are simple and relatively inexpensive to make. However, a means to increase the sensitivity of such recording media, that is, means to decrease the amount of exposure or energy required to record holograms in such media, would further decrease the cost of recording.